I recently bought a Kowa 883 with 2 eyepieces (TE-20H 25X LER, and TE-11WZ 25-60X) and the neoprene cover from CameralandNY.
I selected the Kowa for several reasons.
1- I have a 82SV with a couple eyepieces for several years and it has been flawless.
2- Kowa has an LER eyepiece (TE-20H) 25X for folks like me who wear glasses and for spotting from position (prone F-Class.)
3- Kowa has a couple other great eyepieces like the TE-11WZ 25-60X Wide Zoom and TE-80XWide 35X for general spotting or digiscoping.
4- Kowa has a full assortment of adapters for digiscoping. I like to attach my D7500 to spotting scopes and record stuff.
5- Kowa has 1.6X extenders and astro adapters.
Most important for me:
6- The 88x and the new 99x Prominar have pure fluorite crystal lenses, which I believe to be unique in the industry. No CA.
I hesitated between the 99A and the 883 and ultimately decided on the 883 because of size and weight. I am using the spotting scope from position in F-Class competition and I felt the 99A would be too big and heavy. I already had issues with the 82SV's length, didn't want longer and heavier.
I have just started using it and I am extremely pleased with the optical performance and the whole package. I absolutely love the dual focus controls; they work extremely well from position and the fine tuning is great.
I like the neoprene case for the extra padding, just in case (pun not intended, but it is punny.)
I have several tripods, some heavy aluminum ones, and other lighter carbon fiber one and they work well with the 883. In position, I have been using something radically different and while I'm still getting used to it, it has a lot of promise.