Since machop is rare in your area I would but if there is a machop nest anywhere semi close to you that I would wait to power this up tell you lvl 38 and can get the max lvl 39.5 pokemon but like I said if machop is super rare than yes he will still be usefull maybe a little worse than a C/CC ursaring tho so you might want to try for one of those. Trust me I have one I prefer him over machamp to take out blissey because he is not weak to 3/5 of her moves.
Machamp 100% + BP/CC: power up or not?
My Machamp lvl 17,5 is 100% IV but haven´t the best moveset!
Being Machop appearance pretty rare i my area, I´m doubt about power up this one or not!
I have three Machops lvl20 88,9% (15/13/12; 12/14/14 and 11/14/15).
Keeping power up Machamp or evolve one of these threee machops? All four hatched, of course!
Thanks.

Answers
Man! You have read my mind. The difference in the move set could be and almost always is a decisive factor for the outcome of the battle. You will invest pretty huge amount of dust/candies (like 180K/180pcs.) into the mon. But at the end, you won't be satisfied with the performance it gives during the battle. As for me, whatever rare candies are I keep on stubbornly evolving till I get the optional move set. I got 5 Gyarados evolved and abandoned till I got the 6-th one with Dr.T/OUTRG. After evolving four Machamps I still don't have a needed one. So I keep on moving. Practice shows that the set is matters. Data10 is dang right!