HMMMMMMMMMMMMMM...

room for debate here lol.....based on the initial statement and following examples... I'd say the comparison is subjective... mostly because of the different genres
A boat ...sub... and tank... if there was an airplane like Phil's 190...well that sucker would be bigger than everything lol...so let's divide and separate the genres.... the boat.... boats are for the most part better when big... the level of detail... and the ease of recovery when out of power in the middle of a pond is a definite plus
The sub.... having only dealt with tiny micro models.... I must be a fool... as I think the tiny ones are more fun...for the reasons above....I can play with a mini in a tub or sink... even a fish tank.... if it gets trapped under water...no additional gear is necessary

...my hand is a sufficient DSRV ...now if a big sub lay beneath the water... even at a shallow six feet.... it means I have to get wet

.....in the middle of a pond... for a lengthy amount of time... as drift ...visibility and temperature become part of the equation
Now the tank... Tanks are great no matter what size they are....

Recovery aside from chance visit to the Emergency room for hernia treatments ... is still relatively simple...crashing a big one might make one think about taking up an additional insurance flyer should the collision be in your garage ... someone's auto... or simply running over a foot
Pros and Cons...for going big in any hobby lol....reason it's best to just find what suits one best
ALPHA