You can always resell a RIC but I still recommend playing one first.
If you can manage to play one of these at a local shop definitely do so! However... Rick basses can vary wildly from bass to bass. More so than your typical Fender whatever does.
I've been playing this brand on and off since 1978, so here is my take on how they feel in actual use compared to something more common...
They do have somewhat of a unique feel to them, but if you have ever played a mid 60s Fender Jazz Bass or a reissue of that neck style, that is probably the name brand model that would feel the closest to a 4001/4003 neck in terms of thickness front to back.
The neck thickness varied a bit between the 4001 and more modern 4003s too, but not by huge amounts.
In terms of modern examples...
I just bought a 2011 4003 and its neck is just a tad thinner from front to back than my 2013 Fender American Deluxe Jazz Bass. Rickenbacker fretboards don't taper towards the headstock like a J Bass does so that is one notable difference in terms of how they play at the headstock end of the neck. In that regard the amount of stretch on fret 1-3 on the E feels closer to a P bass in terms of fretboard width to me, but more comfortable personally than a P on my fretting hand.
Personally, I have no problem moving back and forth from a Jazz to a 4001/4003. Some of my more involved and complicated original bass lines were written, performed and recorded on a 1972 Rickenbacker 4001. I chose that instrument for the job over the 76 Fender Jazz Bass I owned at the same time. I just felt I could play faster and longer on my 4001 than on my J Bass, even though my Jazz was a killer bass in its own right!
Hope that helps a bit if you have never actually picked up a Rickenbacker bass before. Hopefully you have played a number of Fender Jazz basses before, because as I said, that neck is the closest over all to the feel of a Rick. Sounds wise too, a good J Bass comes the closest to a Rickenbacker sound without being one.
