I have an R71A, and I feel the two are very similar in design.

The R71A is great receiver; however my little Icom IC-703 (approx $300 used)
which is very portable has fantastic
sensitivity, built-in antenna tuner, draws half-amp on receive.

eham.net has more reviews of the 751A.

I really feel the general coverage receiver in a ham band transceiver is
more value for price paid than a standalone receiver.

Gary
K4GPB