I've got the brushcutter, strimmer, mower and cultivator. The brushcutter/strimmer is good, and I'm considering buying an extra strimmer head so that I can have a quick-change between the two rather than having to fiddle about unbolting the various bits to swap them out ATM. The mower is useful on small areas of grass like paths and does a lot better job than a strimmer for that... There cultivator is a bit light but it's not intended to replace a Howard Gem so don't expect it to... I find it useful for seed-bed preparation where it can turn a strip of dug soil into a very fine tilth very much quicker than I can by hand, it's also good for weeding between wider spaced rows, but modern planting techniques are frequenly too close together for it to be used there.
BTW, Ryobi are notorious for not starting as per manual, so you might need to experiment....