I use a Porta II quite a bit with an SW 100ED and I find it works very well. The slo-mo controls are fine but you may wish to install some more flexible cable types. Just take a little time to balance your scope and set the drag. A couple things I did change as "personal preferences". You don't have to do these and the stock Porta II will serve you just fine.
If I'm doing high magnification stuff, like splitting binaries, I mount the head on an EQ-3 steel tube tripod (it's a direct bolt-on. No mods needed) like you see in RTLR 12's post above. The stock Porta II tripod is fine at lower magnifications but gets a little shaky higher up.
Secondly, if you want to avoid having the Vixen dovetail on your scope pockmarked with mounting and safety screws marks over time (Vanity, vanity, all is vanity), replace the stock saddle with something like a Williams Optics clamping unit: https://williamoptic...tail-plate-90mm
I have other mounts, but the Porta II is generally my "grab n go" favorite.
Clear skies and be well.
Edited by BlueMoon, 29 October 2020 - 06:06 PM.