David Best has a document that goes into detail on both the Felder and Lamb parallel fences.? That being said, there are two things that stopped me from going with the Felder parallel fence:
1. While you can do up to 39" parallel cut, the Felder item is really long and becomes a serious obstruction when working around the saw.? Storage of this really long and heavy item can be a challenge as well.? Even the short Lamb parallel fence can be somewhat of an obstruction when working around the saw, but it's much easier to work with.
2. The height of the hairline pointer on the Felder site gauge can easily cause your result to be up to 1/32" off (this is enough to cause mis-fitting of wood during assembly!!).? Actually, you can be up to 1/16" off if you're not paying attention.? This is the same problem with the Felder non-DRO stock flip-stop on the crosscut fence.? Frankly, it's a pain to use.
The Lamb parallel fence is actually quicker and easier to mount/un-mount when compared to the Felder.? See Felder demo here at the 14:23 minute point on this video:
These are the main reasons I went with the Lamb solutions.? I have been extremely impressed with the quality of materials as well as the design/engineering of the Lamb devices.? I have both the parallel fence and DRO flip-stop from Lamb Toolworks.? These are excellent devices and well worth the money.? In reality, if you are doing a cut that is larger than 24", the material is large enough where the crosscut fence can ensure a square cut.? In my situation, I was able to mount the measuring tape on my Lamb parallel fence to get a 27-1/2" cut.? The actual max distance will vary depending on your machine/setup.? In my opinion, the only time where you would need the Felder solution is if you are doing a larger parallel cut when the material has an uneven or rounded end (where the crosscut fence becomes useless).? I really don't see this scenario happening for 99% of the projects you work on.? Alternatively, a track saw could be the solution for that scenario.
Be aware that the edge of the sliding table is not 100% perfect.? There can be a 0.010" to 0.020" variance on the flatness of the mounting edge for the parallel fence.? This is actually pretty darn straight for an extruded aluminum product.? See here:
You can see that the edge goes to 0.010" pretty quickly and stays there until you get to the end of the sliding table where it drifts to 0.020".? I typically mount my parallel fence around 3-5 feet away from the crosscut fence and have it calibrated for that area.? I have the analog version and have had no problems with the accuracy.? The analog version is actually quicker to set for a particular distance than the DRO version.? For example it's very fast to slide the fence to exactly 10-1/2" and lock it in.? With the DRO, you have to move slowly and try to adjust/tap the rail until it's right at your chosen distance.? Though, if you're splitting hairs and 0.03" variance matters, then the DRO unit is probably what you want.
-Aaron
