Hello Dominic, It really depends upon what you intend doing so please note the following: If you want to work the satellites with a transponder - Then the only main satellites with a 70cm downlink are FO-29 (analog,ssb,cw ) and SO-50 (Fm ) and if it is operating AO-27.
AO-7, AO-73 (Funcube -1 ) ,Funcube-2, have 2 metre downlinks and of course with reasonable coax the loss is far less in this band. . Future launch of Fox-1A will be also be 2 metre (FM ) downlink.
For data AO-73,UKcube -1 + Funcube-2, UO-11, DO-64, ISS, EO-79,EO-80,NO-44 etc operate with a downlink on 2 metres.
Many of the cube sats. built by Universities and experimental have a downlink 435 and 437 MHz regions and of course numerous modes and baud rates. Trusting that my information will assist you. Ken Eaton GW1FKY