Terry Q summed that up nicely. If you can get both, do and put te 1617 in the table using the fixed base. You have to order a small key to raise and lower it, at least for the fine adjustments. Save other for freehand use. If you can only get one, I'd go for the 1617. Price on all power tools is about 40-50 percent of a new one, assuming that model is still available. Check the 1617, which is often on sale for $200 to $220 brand new in the EVSPK kit that has both the fixed and plunge base, including two collets. If it's the router motor with just the fixed base, and used, should go for much less than that.
The MRF23 is a nice router, but I don't like it as much as the 1617. But it is nice to have a separate machine so you don't have to take the motor out of the table to use it with the plunge base.
I am finding mysef using the Bosch Colt (1hp) for many of my freehand jobs, including cutting shallow hinge mortises and doing simple roundovers. It can be had new for around $90 on sale now at Amazon. It's $186 for the kit with the plunge base. Makita also makes a nice 1.25 hp (trim) router with a plunge base for $140 on Amazon (model Makita RT0701CX7 1-1/4 HP Compact Router Kit). The smaller routers are also good for making signs, although you will want a double handle oversize base so you can control them as you carve lettering.
I've attached some pictures of the 1617 and Colt in the EVSPK kits. The third picture is the Makita compact router kit that comes with a plunge base and an edge guide. Fourth picture is of the colt wide base for sign making. The low handles makes it easier to control.
The more I do, the less I accomplish.