I'd steer clear of cheap Chinese motors -- in my experience the quality varies wildly from one sample to another so it's sometimes a bit of a lottery.

I've got an ASP52 in my Katana profile right now and it's got gobs of power but it's not fun to fly. Most of the time it's fine but every now and then when you come in and pop it into a hover at knee-height the engine will stumble and you'll end up busting the rudder (again).

This is an old airframe so i don't care -- but there's *no* way I'd risk a new bird (especially something like a Primo that you've got to build from a kit) to anything other than a Saito, TT46Pro or OS.

How much did your Primo kit cost? If your cheap Chinese motor dies at the wrong moment you could end up wasting that money by totalling your plane -- leaving you with nothing but a broken bird and a crappy motor. Even if the motor doesn't kill the plane, an inconsistent running motor takes all the fun out of trying to fly 3D because you end up having to fly defensively, always worried that a stumble or hesitation could result in a crash.

I learned a long, long time ago that cheap Chinese engines are a false economy. Unfortunately I lose a plane or two every now and then when I wonder if things have changed and take a chance on another.

The last bird I lost to a Cheap Chinese engine was my lovely Primus 50 clone that was lost to a crappy SK50 -- failure to transition properly. That same plane had flown for four years (first on a TT46Pro and then on a Saito 82) without a scratch -- but within three weeks of fitting the SK it was broken clean in half. I should have known this engine was a lemon when it came without any usable threads in the glowplug hole -- I had to tap them myself because the tooling they used was obviously so worn that the tap barely scratched the sides of the hole. I gather that SK and JBA are made in the same factories and share many castings/tooling setups.

Funny enough, the SK90 I also bought at the same time is *perfect* -- but I've heard from a few other SK90 owners that theirs are nothing but trouble. As I said -- the quality of these cheap Chinese engines just varies too much from one unit to another.

Not worth the risk (IMHO).

Should you buy a JBA you *might* get a good one, Ed obviously got a good one -- but there are very high odds that you might also get a dog -- which means you'll have wasted that money and still have no suitable engine for your Primo.

Remember that there's usually a *huge* difference between price and value :-)