I am interested in your Sharkskin or Textured fly lines from the spec sheet, I can't tell the casting difference between the Sharkskin GPX or Sharkskin Ultimate Trout WF - both sound good. Here is my fishing profile...
I fish 70% Nymph with split shots, 20% Dry (small 14++) and 10 % Streamer on 5wt Orvis Helios (mid- flex). Currently, I have a 6wt R*& G#$%^ on it now but it is too much for the dry flies and I'm not really happy about the feel of the line, lots of memory, not too fast. I fish 40-50 days a year mostly in California including Fall River (Spring Creek) where I need a very long presentation (70 feet is common). Ok...what would your recommend? I am open to the new texture line too? Any suggestions would be appreciated. BTW does the Ultimate Trout line have the dry tip technology?
To break things down let's separate the lines out a bit. It's best to describe the technologies and the tapers separate.
Sharkskin lines differ from the new Mastery Textured series two ways. First, the type of textured structure on the surface of the line and second, how much of that structure is present. Sharkskin lines have a diamond shaped pattern covering the entire circumference of the line. This diamond pattern is fairly aggressive, or rather, it has large peaks and valleys. Mastery Textured lines have a dimpled structure similar to those found on a golf ball. Also, the dimples do not cover the entire circumference of the line but instead are evenly spread out around the line's surface. Having ANY structured surface on a fly line will enhance the performance of the line in four ways. It will make it easier to cast, make it float higher on the surface, make it last longer with normal wear, and make it have less memory. The more radical the structure and the more of that structure present, the more these characteristics are enhanced. The two lines also differ in how they feel. Sharkskin, due to its more aggressive structure, feels much more course in the hands while a Mastery Textured line feels much more like a conventional smooth fly line.
Now on to the tapers…The GPX is an all around line. It handles anything from small dries to big hoppers to indicators to streamers. It's a half line size heavy, so if you're buying a 5 weight, you're essentially buying a 5.5 weight. This is a nice feature when using it with a fast action rod - which may require a bit heavier line. Also to note, the GPX comes in both a Sharkskin version and a Mastery Textured version. The taper is the same in both series, only the type of texture on the line differs. Some drawbacks of the GPX are that some users may find it a bit too aggressive for fine dry fly fishing. They also may find it not as accurate as some of the more precise line series (like our Mastery Trout taper).
The Ultimate Trout was made to be a great all around trout line as well. However, it tends to lean a bit more toward the lighter stuff than the GPX. For instance, it is a true 5 weight. Also, it has a bit longer front taper, so it is a bit more accurate and works a bit better for the small stuff. Can it throw nymphs and indicators? Absolutely, however, the GPX can probably do it a bit better. It does have dry-tip (as does the GPX) and also stream lined loops on the tips for quick leader connections.
Based on what you plan to fish, I'd recommend the GPX. Based on what you've told me (70% nymph fishing), the GPX sounds a bit more suitable for what you're doing. Obviously, the kind of rod you're throwing and your casting style plays a huge role. However, the GPX is one of our best sellers for a reason - it's just a great all around trout line! The type of texture on the line is up to you – Sharkskin if you’re looking for something very extreme or Mastery Textured if you’d like something that feels more like what you’re used to.
That's a lot of information but I think it should help in your decision process. The distance you're presenting flies (70 feet) should be attainable with both lines and both are pretty comparable in long distance.