A bolt on bucket edge is typically for protection of the bucket lip against wear. If the bolt on edge wears badly, it is easily replaced. Personally, almost all CUT's never see enough FEL use to ever wear out the lip of a bucket. Maybe someone doing snow removal on cement could wear out a lip on a CUT FEL. A bucket edge does give some extra strength to the lip but the foundry bucket is more HD and IMHO does not need the bolt on edge for strength.
I have used both tooth bars and those with individual teeth bolted directly to the bucket edge. The tooth bars result in an overall thicker edge (bucket lip, thickness of tooth bar and bottom of tooth extends below bucket). Therefore, toothbars do not dig as well as teeth directly bolted to the lip. IMO, tooth bars may take 25% more effort to dig compared to direct bolt on teeth. (seat of the pants measurement
) But, a toothbar still digs much better than a smooth bucket. If you are planning to leave the tooth bar on most of the time, consider getting direct bolt on teeth to the bucket lip. Direct bolt on teeth should also be cheaper than a bar. It is still easy to back blade with a toothed bucket, especially if the teeth are flush with the bottom of the bucket. A bolt on tooth bucket will also act like a smooth bucket if the teeth are flat to the ground. A tooth bar bucket will not perform like a smooth bucket because of the thicker front edge.
The JD foundry bucket has a thicker top edge. JD may make a bolt on grapple for the foundry but I do not know. Bobcat does have a bolt on grapple for their regular buckets. Maybe JD does? JD does have a grapple fork bucket and maybe that could fit on a foundry bucket? I had foundry buckets on both my 3720 (66") and 4520 (72"). Loved them. It was a recommendation by a fellow TBNer and I am passing it on.
Really consider the JD skid steer carrier attachment. In the long run it maybe cheaper. The foundry bucket is cheaper than the JD HD bucket and will save some money. If you ever plan to get forks, the JD CUT forks will cost much more than a new, similar skid steer type forks. Easy to find good used skid steer forks and save a lot of $$. You will almost never find a pair of used JD CUT forks. The amount of $$ saved by buying skid steer forks will pay for the skid steer carrier attachment. I find forks almost as useful as a bucket.
Tire width. I owned a JD 3720 with cab and R4 tires. Set to their widest at 59"s. I had 2 CUTs prior to that one. That was a scary tractor on hill sides. 5 minutes after I bought it new, I tried a little digging on a dried up pond. I was on a mild slope, was digging and spun the down side tire deeper. No rear
ballast or weights. I thought it was very close to tipping. Sphincter was tightened to maximum. I think because the bucket had dirt in it and was on the ground may have been the only reason it didn't tip. I did not feel I could raise the bucket at all. I did lower the bucket and raise the front end slightly to put more weight on the rear, used the bucket to push and managed to slowly back out of a bad situation. The 3000 series demands ballast in the rear (in tires, wheel weight, or 3pt attachment) to be safe and I feel more width in the rear. I now have a JD 4520 with identical cab. It sits higher but has R1 tires set at 71-72" and about 440 lbs of rear rim weights. It feels 3x more stable than the 3720 despite being taller. Long story short, really consider setting the tires wider than 60".
