I think the cheapness factor was what was offputting to myself, initially. But after reading the forums, here, as well as looking at the alternatives (and the stories people had about THOSE), and seeing the result in motion (thanks to YouTube), I decided this was a GREAT value. Even if you have to spend a coupla hundred bucks extra to make it sing. One comment I saw consistently is that even the more expensive motors from other sources still come with equally cheap peripherals (throttle, etc.).
I can't speak for the front wheel kit (I still don't like the idea), but the rear wheel kit DOES come with some heavy keyed washers which will definitely stop the motor from spinning in the forks. Everybody complains about the rim and tire they give you, but a decent rim with double-wall construction, spoke eyelets and machined sidewalls can be had for $35. I don't know what a bike shop would charge to relace the wheel for you if you don't know how, but a good wheelwright can usually knock the job off in just over an hour. And a perfectly serviceable Kenda tire and tube can be had at Canadian Tire for just over $20. You can spend more if you can really tell the difference (there are tire snobs out there), but Kenda is what came on our Giant comfort bikes, and they've been great.
Why batteries aren't offered with the kit...
I would think the two biggest reasons would be shipping weight, and possible complaints... Despite all of the talk about NiMH, NiCad, and various flavours of Lithium-based (expensive) batteries running about, the most common battery used in this application is still the SLA. They're inexpensive, and do the job just fine. But they're heavy. I've put together two SLA packs (three 12V batteries each), one being 9Ah and the other 12. The former weighs about 17 pounds, and the latter 26. Pretty beefy. SLAs are great batteries for the dollar, but do best in applications where they are discharged over several hours and aren't consistently run to exhaustion. But they CAN be deep cycled repeatedly (as is the case with an e-Bike), and will perform just fine on the quicker discharge - though they'll deliver a bit less than their rated capacity. Still - their life can be short. You might get a season out of them before buying new ones depending on how you use them (they won't fail, but you'll notice they just don't hold as much of a charge as they used to, and the decision to replace them will be elective rather than necessary). And I'm sure THAT'S the reason a lot of e-Bike kits don't come with batteries. Someone who uses the bike a lot for LONG runs where the battery is completely spent when they get home is bound to feel ill-used and complain when they're told they need new batteries in a matter of months. I'd like to know how people make out with these cheapie Schwinn electric bikes that Canadian Tire is selling. 24 volt system with SLA batteries, and not a lot of capacity (meaning you're likely to run them down more often than not)... and the replacement packs start at $129. These bikes are almost a loss-leader to sell batteries, if you ask me :-)
Where to buy SLAs? Anywhere that sells electronic components. One thing I did note, though... And forgive me - this is going to be the THIRD time I've mentioned Canadian Tire in one post (I'm really NOT Ted Simonette, wanting his old gig back) - they carry replacement batteries for an inflatible watercraft they sell (A Sea-Doo product that inflates into the shape of a jetski). The unit is a 12V, 12Ah SLA designed for deep cycle use in the boat... They sell these for $39 each. Haven't tried 'em, but it seems like a safe bet and the price is in the middle of the pack to what you can pay for a battery of this capacity. You need THREE of them, remember.
There is a trade-off, here. My thinking is that small batteries with "just enough" capacity for your usage pattern - this, in order to save weight - is likely to result in more frequent replacement. Buying a bigger battery that you only need to "top up" when you get home will give you a lot better service life. The proof will be in the pudding as I compare the 9Ah pack to the 12.
A battery charger comes with the kit. I don't trust it. I think it might be an OK fast charger for batteries of a different technology (don't know), but after having monitored it on SLAs, I can tell you that it is inclined to WAY overcharge them, and doesn't seem to control charge current and voltage adequately toward the end of the cycle. You certainly shouldn't be able to HEAR your electolyte bubbling when you start to approach a full charge. I've got another kit on the way, so I'll see if that charger does something different, but I've also ordered another battery charger that I'm more comfortable with... See
http://www.vdcelectronics.com/batteryminder_36v_1_3a.htm.
Apart from being a decent multi-phase charger (with a reasonable maximum charge current of 2.7A), it's also alleged to incorporate a patented "reconditioning" technology that claims to de-sulphate the plates by running a high frequency, low-voltage, signal through the batteries while in maintenance mode. Maybe the effect is something like an ultrasonic jewelry cleaner, but different - dunno. It also comes with an optional temperature sensor which you can attach to the batteries. If something heats up, it'll shut down. Good feature. And, by registering the warranty, they also send you a little battery condition guage for free. A neat goo-gah to quickly look at individual batteries in the pack (don't connect it across the whole 36V array :-).
Anyways, a charger that I can plug in and walk away from (and leave the batteries connected to indefinitely) is what I was after. This seems to be it.
So - as for the whole kit, and your question, "is it any good?" Leaves a bit of margin for interpretation, but from this guy's perspective, it's good value.
FWIW.
Cheers!
