The thing is, you don't need to drop $1000 to get a 4-channel scope these days. The Rigol 1054z is a 50 MHz 4-channel scope for $350. The hardware itself is excellent, and the software is very polished. It's basically the gold-standard of entry level scopes, and completely shook the industry up. Yeah, a current probe and related accessories is gonna set you back another $100-150, but you'll end up with a far more capable platform.
Don't get me wrong, if you know what your waveform should look like, a single channel scope can be a very useful tool. The small and compact nature of the u-scope certainly adds utility to it as well. However a 4 channel scope can let you look at 4 ignition traces at once, compare ignition events to what the crank sensor is doing, or compare any other sensor against another. It's just a far more powerful tool.
It really comes down with how much you plan on doing with a scope. If you plan on doing basic things, value portability and don't care for advanced functionality, than the $350 u-scope is certainly a good value, especially with the included current probe. However if you think you might want to do more with a scope and don't necessarily need portability, something like the Rigol 1054z for $350 + $150 in accessories is the way to go.