You can get the first style you link to in either horizontal or vertical orientation - same as the (cheaper) Iskra type. The Iskra are good and good value. My point was just if you want nice, fancy parts for your builds you can often get even fancier than found in a typical DAM pedal - certainly in terms of the passive components (not that it will make any real impact on how it sounds of course... mojo in guitar fx and amps is all about the looks and how you feel about something after all
).
(The ge transistors, often unobtamium, are a different matter of course).
The Iskra have carbon tracks I'm sure; the Spectrol are cermet - which I read somewhere is better for a trim pot (which you set and forget) as it is more stable over time/temp. I also think the Spectrol are made to somewhat better tolerance and that they are completely sealed. Not that any of that makes any real difference for your typical stompbox circuit - I'm just saying it's a fancier, pricier component. I've used them once or twice for some pedals I've wanted built to as high a quality as I could get them.
Marshall, DAM, any manufacturer chooses components to some extent on cost of course. For a hobbyist building a one-off stompbox you don't have to be so constrained - 30-40 plus pence for a Spectrol or 7 pence for an Iskra... it's different if you're ordering hundreds or thousands of the things of course.
The multiturn type of trimmer (that you've found annoying to use) are for precision, fine tuning of resistances - I can't think of a stompbox that requires one, certainly no DAM (i.e. a remake or development of a 60s or 70s fuzz box).
I've never stripped a trim pot - were you pretty rough with it? That's a miniature preset I think - so possibly quite delicate. Trim pots are designed to set and forget by the way - with maybe the odd recalibration. I don't think any trimmers/presets are intended to be rotated too many times.
That last one is probably much too fancy and wasted in a stompbox - just my opinion anyway