"IFR equipped" can mean anything, so is meaningless.
"Airways equipped" means it has a full set of IFR instrumentation and is useable for Class A IFR flight - assuming you have the rating for it.
If you plan to fly IFR in IMC with your IMC rating, then my advice would be to ignore the "you could get away with..." and go for something fully airways equipped.
To get me to fly in IMC, which I do often (including some today) I insist on 2 VORs (at least one with ILS), DME, transponder (with Mode C or Mode S), marker receiver, ADF, 2 COM sets (all FM immune), AH, DI, Turn Coordinator, 2 altimeters, and a clock. You might also want an IFR-approved GPS but that's sort-of optional although nice.
Yes, I've done IFR approaches with only an ADF and one VOR, and it's not a good idea.
If you're going to use an IFR-approved GPS, then plan to spend a LOT of time with it, getting to know how to drive it. At 2000 feet in filthy turbulence isn't the time to start trying to work out which button to press...