There are a couple of things to consider. Budget for one and Depth Raider is less expensive approx $450 vs $750. Regardless check for some show special pricing that happens this time of year. I think the brand of rigger may matter a little. For example the larger rollers on Big Jon vs Walkers could make a difference with respect to cable abrasion. I think it is helpful to angle the downrigger arm when retrieving to minimize drag and helps the cable lay down smoothly.
For me I think the concern re blow back due to thickness of cable is a bit over blown. pun intended. I choose to run my probe rigger as the shallow one of three. This generally requires deploying less than 60' much of the season. Plus not next to the bottom and risk loss.
I've been using a Depth Raider since it hit the market I've only replaced the cable once and that was due to downrigger lines crossing and damaging the coating.
For me the value of speed and temp can not be overstated. Either unit will improve your catch and fun on the water.
Thanks for input. Next question is when using these units I've been told that the speed at the depth will increase when going into the current. If wanting to go say 2.4 to 3 do you slow down to achieve that or just let it be. Just trying to understand how to read the info from these units. I know temp is a big thing also.
Goal is to find a speed that the fish like and maintain that speed regardless of the direction you are trolling. That can change daily or within the day so pay attn if bit on a turn and whether on the slow or the fast side of the turn. So in order to maintain speed when going with the current you generally need to increase your speed over ground to keep you lures at the same speed. The reverse is true when going into the current. The velocity of the subsurface currents are ever changing as well as the direction it is coming from. I don't pay a lot of attn to my gps speed but watch the down speed on my Depth Raider.