I've got one and like it fine. They seem to be very well designed and constructed, but you're right: it is tougher to see what's in the filter. I actually used an old wood chisel, hammer, pliers and some tin snips to open up my filter at my last oil change---a messy (and potentially dangerous!) process.
Do a search. There's apparently a device available that's a kind of "can opener" for spin on oil filters. I've considered getting one...forget what they cost.
|