As a pressure treater, I generally "recommend" whatever a coating manufacturer says will work best with our products. As a DIY'er and builder of many outdoor projects with PT, I often use solid and semi-transparent oil-based stains. I find them far superior to paint.

We recommend applying a topical water-repellant annually or biannually. Whether that is a solid or semi-transparent stain (or water sealer such as Thompsons), that's entirely up to you. The obvious sign that you need to reapply is weathering of your deck and / or color fading. In general, I'd go right over the solid stain with the same color. Changing manufacturers won't be a problem, but you might run into slight tone variations. I wouldn't recommend going over an older faded solid stain with a clear waterseal product, as it'll just highlight the faded color underneath. On a weathered and faded deck though, you can probably get away with applying a different color of your choice in a few years over the old color.

I'm an oil-based kind of guy, and I have the best luck with those products outdoors. Hope this helps.

Teh solod colour behr's will last far longer than the Thompson's. T watersealer ios basically just a thinned down wax solution that dies from the UV sun and wear in six months .

The problem is that if there is a residue of Thompsons, it can interfere with the bonding iof the new stain. Clean and sand if need be to increase bond.

How long it will last is anybody's guess, since nobody knows how much foot traffic it will get to wear it out - or ice and salt, for that matter. Three years is doing good for a deck.

Irf you choose to change colours later, I wouold recommend sanding this one off. That way, you will get a better bond directly to the wood, and if it starts to wear through, you won't be seeing the old colour under it.

Excellence is its own reward!

JayF and Piffin: thanks for the comments. They are very much appreciated.