@tele - Nice thread here.
The more non-poly/non-gut strings I test, the more I appreciate what Tecnifibre has achieved with their PU400 matrix (used on almost all of their multi's/multiesters). Even notched, it very often retains nearly-100% of its sliding ability, and does so against more types of opposing string surfaces as well -- unlike many (most?) other initially-slick synthetics, whose surfaces tend to be a separate coating, polish or jacket/sheath, where even the slightest bit of wear often kills snapback entirely. On the other hand, the PU400-based strings with that surrounding matrix being the same material all the way from the surface to deep within the string, tends to retain its snap way more effectively and for much longer (kind of in the same vein in the world of poly of how high-percentage cross-link esters like Wilson Revolve and Grapplesnake Tour M8 derive more of their slickness from the core co-polymer material itself, and retain the same coefficient of friction even as the material notches all the way to the core).
On that note, I see very few combos that offer both poly/poly like snapback and high snapback longevity. In my case, one of the best has been RPX/Cream, which has a bit higher-percentage poly overall than your setup of HDMX/TPP, but exhibits incredible snapback for pretty much the entire life of the string bed (I was stringing it for a 4.0-ish client who would routinely get 50+ hours out of a single string job, with full snapback all the way to the end). I think that result is owed to how well the PU400 interacts with the wax-infused finish and softer surface hardness of Cream.
TL;DR - On the flip side, a recent example of an initially-outstanding combo that last -- very depressingly so -- was AK Pro CX / RPM Rough (in my playtest Strike 100 16x20). For the first 90 minutes or so, oh my god, I thought I has discovered the holy grail. I'm not exaggerating when I say it had
the most snapback-inducing spin of any string combo I've ever tried,
including poly/poly and gut/poly hybrids. Like, illegal levels of spin -- curve and kick on my serves that I've simply never seen and ground strokes that were bouncing over head-level, routinely. But at about the 2 hour mark, once the silicone coatings on both strings started wearing off, snapback pretty much ground to a halt, and the hybrid became mediocre at best. Which is the frustrating part of so many of these combos, that start off with incredible characteristics, but usually lose them in very short order; typically 3-5 hours, or less.
As such, I've come to a point where I tend to prefer the most "sustainable" setup, where the performance may be lower to begin with, but can be sustained to a much greater degree and longer amount of hours (preferably 10-20 hours, at minimum).
All said, I'm with you on the hunt, and will post any further discoveries here, both good and bad, as I make them.
Current strings on my radar as potential mains to a poly cross:
- Volkl Power Fiber Pro
- Yonex Dynawire
- YTEX Sintex
Potential poly crosses to evaluate:
- MSV Swift (White
and Black)
- Toroline Snapper
- Toroline Wasabi X