I love my boos gt10 and have owned all the digitech rp1 5 10 20 30 and silver rack valve fx and I rate boss as now being a better unit but not when the rp30 was out. I tried every unit in the shop for hrs ..before buying the gt8 then the 10 after has it had a better looper and extra ctr pedal plus interface was easier ,,,I was dissapoited with the looper but the rest of thew unit is a killer box so I bought a rx20xl with the two pedals , and apart from no midi sync which is hard to keep it looping to a drumloop externally playing (any tips if you have one pls) but its got loads of live versitilty that the jamstations just hvent got , tempo tap and clear overdubb on the fly , plus guid tones drumloops built in , a center cancelling to rid vocals and some guitar off audio plus the ability to slow guitar phrases right down and keep the pitch makes it great for learning stuff too, boss was clever with this , the 50 would be great with midi and stuff but the price is too high and it to big too

Ive said my peice so peace out ,