I bought an Enco rf30 back in the early '90s. I have a Shars 440v vise on mine, which works for me. A 5" would be fine, if you want the extra capacity, some even use a 6", but seems overkill to me. The vise you are looking at is rated in thousands, whereas the 440v or 550v are rated in tenths. Although a bit more money, it sure is nice to be able to put a piece in the vice and not have to worry about if it is as straight or square as it could be.
A modification I consider mandatory is to add a DRO to the Z axis. The quill has enough slop that as soon as you release the lock, you lose your position, making the dial virtually useless. A vernier caliper or Igage will work fine.
Another improvement I highly recommend is to add a 3 ph motor and VFD. Mere words cannot describe the improvement of being able to adjust the speed at the turn of a knob compared to having to open the belt cover, loosen the tension, move the belts to the required pulleys, tighten every thing back up, and close the cover.
Another thing that has aggravated me to no end is having to wrench on the drawbar, bang it loose, and unscrew it to change collets. Having no spindle lock makes it even worse... An impact wrench makes it easier, but still a pain.
Fortunately there is a solution to this problem, see my post : Power drawbar for RF30 in the Enco, Jet forum.
A modification I consider mandatory is to add a DRO to the Z axis. The quill has enough slop that as soon as you release the lock, you lose your position, making the dial virtually useless. A vernier caliper or Igage will work fine.
Another improvement I highly recommend is to add a 3 ph motor and VFD. Mere words cannot describe the improvement of being able to adjust the speed at the turn of a knob compared to having to open the belt cover, loosen the tension, move the belts to the required pulleys, tighten every thing back up, and close the cover.
Another thing that has aggravated me to no end is having to wrench on the drawbar, bang it loose, and unscrew it to change collets. Having no spindle lock makes it even worse... An impact wrench makes it easier, but still a pain.
Fortunately there is a solution to this problem, see my post : Power drawbar for RF30 in the Enco, Jet forum.