honestly, I have had very few shocks on any model that didn't fail at some point...either bending the shaft or leaking.
But, my team associated SC10's shocks work very well. The truck has over 10 hours of runtime and the shocks have yet to fail. They are the sc10rs shocks. I am not sure of the length of your shocks...you would have to measure them. Usually online (sometimes threw google search) you can find the length of a certain shock in MM. If you measure yours in inches, just use google to convert to MM. You can run slightly shorter shocks, you will just lower the ride height and lesson the shock travel amount. so the proline guy likely meant a downgrade as in lesser shock travel....less travel means less to absorb shock from jumps.

I know many like the proline shocks. I haven't owned any that were new...so I cant really say. I had some used ones on a used slash I had bought, and they were toast. one had a bent shaft and the others had leaked and were dirty. But who knows how old they where.