Yeah the funny thing is you don't need the 30mm tube to transfer light. Light transfer and brightness depends on the size of the objective lens and quality of coating. The fad for 30mm tubes is just that: a fad.

I have four DR's with scopes:

.375 H&H Flanged Mag. topped with a Schmidt & Bender 1.25 x 4

.375 H&H Mag. topped with a 1.75 x 6 Swarovski

9.3x74R topped with its original 2.5x Zeiss Zielklien and an alternate 1.5 - 5 Leupold

and a .300 Win. Mag. topped with a 1.5 x 5 Pentax.

The scope you choose depends on several factors:

* Caliber and intended use;
* Barrel configuration (e.g. what will actually fit);
* Size of rifle compared to scope (not top heavy);
* Budget;
* Etc.

For example of "what will actually fit" I can point to my Winkler .300 Mag. It came to me topped with a 1.5 x 5 Leupold, but the eye relief just didn't quite suit me. I had the 1.5 x 5 Pentax on hand, and it has a longer tube. I popped it on in place of the Leupold, and it proved to be perfect. The little Leupold is a grand scope but very short.

Long ago when I had a Valmet system like yours I topped my .30-06 barrels with a 4x Weaver, which did fine. My 12 over .222 barrels were topped with a 2 x 7 Redfield in the Valmet QD mount.

So there are lots of issues to consider. High on the list should be ergonomics. Improper eye relief ruins a rifle/scope combination.

Good luck,
Curl