After playing an Alvarez Yairi that I bought new in 1978, I now have permission to upgrade my guitar. I have been looking at the Martin guitars and I am seeking input regarding the various models.
What are your thoughts about the D-18, D-28, and the HD-28?
Should you spend what you can stomach?
Just curious what your experience with the Martin guitars has been and if you had it to do again what would you do differently?
Mike
Iāve never played a Martin, I believe @Flatpickin_Libby has a D-18 though and sheās said a lot of good things about it.
Iām not as much of a guitar player as @Flatpickin_Libby, but we both have the same guitar - a Martin D18 āSinkerā. I personally prefer the D18 (Mahogany) over a D28 (Rosewood) but thatās personal preference.
I am partial to hogs as well. Rosewood sounds lusher, but I often prefer mahogany. I have one that is madagascar rosewood, and I think it sits kind of between mahogany and (east indian) rosewood in tone.
If you want it for bluegrass, my personal preference is for adirondack topped mahogany. In Martins, that would mean a D18-GE or D18 Authentic (or a similar custom like one of the Gruhn models). The Authentics seems expensive, but if you had one built with that spec, it would be much more expensive. Oddly enough, what I am saying is that the Authentics are actually a bargain. With that said, I love other guitar tones and shapes as well. Lots of bluegrass folks like rosewood. If you can get to a great store, just go play a bunch of them and the guitar will pick you.
Great quality and sound in those Martin choices. They just announced the super dred, too, if you want or can tolerate a bigger box. My recommendation is play each and pick the one that you personally like best. Also, consider ordering from the custom shop to get exactly what you want in woods and inlays, etc. Iāve watched their staff working over many visits to the factory and the workmanship is superb.
Martins have long been the āgold standardā in flat-top acoustic guitars, but come at a premium price. I own four, including my D-28 bought new in 1965, so I know the brand. I feel that better value can be had in other marks, such as Larrivee. If you want to pay a premium price then consider a Collings, Bourgeois, or Santa Cruz. They will hold value and be recognized for quality boutique builds. Best ābang for the buckā is probably in the Chinese brands like Eastman or Recording King. Benās store carries both and can certainly give some good advice. There is certainly an advantage in being able to play an instrument prior to laying your money down unless you have a trusted source.
Find a shop where you can play them. I went shopping for a Martin D28 a few years ago. It turned out to be my 3rd choice after listening and playing a lot of fine guitars. I came home with a D18 and love it. A couple of years later I really wanted that rosewood sound and found a used Eastman E20. It was about a third the cost of the Martin and gets compliments everywhere I go.
Iām not as much of a guitar player as @Flatpickin_Libby, but we both have the same guitar - a Martin D18 āSinkerā.
Timothy is as much of a guitar player as me 
but yes I highly recommend the Martin Sinker D-18s!!
Thanks for all the great input! Half of the fun of getting a new instrument is the search for it!
Mike