Yes indeed. History mirrored in FoGN for sure with the 33eme Divisione de Napoli !!
My own Neapolitans have featured in a series of army-mix experiments throughout the past year. Initially I bought the 33eme Division as just the 3 small poor conscript Line Infantry units along with the average drilled Wurzbergen artillery as a cheap allied division that got me out of having to buy any French conscripts (and therefore allowed me more focus on how the rest of the divisions operated togther). It had the major benefit of also providing for a better colour mix than the French bleu. Then I got briefly (and successfully) led astray by the Andrew-Hunter-inspired 2 large French conscript units each with an artillery attachment (supported by a small 'vanilla' French conscript unit) as front-line combat troops and dropped the Neapolitan Division altogther.
After some badgering by other players about how truly great "guard" were, I started including the Neapolitan Garde d'Honneur LC into the 33eme Divisione as a trial followed by then also including the Neapolitan Velites a'Cheval LC. The main benefit is that you can provide for all the compulsories in the 1812 French list in the one allied mixed division (apart from a unit of light infantry and a unit of veteran/drilled line); thus, the 33eme Neapolitan allied division makes for a cost effective additon into an army mix. (The two army mixes I have posted on other threads - the grand battery and the panzer division - both feature the Neapolitan division.)
Then I started on experimenting with including 1 or both units of Swiss just for their red coats - initially as superior drilled, but latterly as average veteran, and always with an artillery attachment (mostly for defensive concerns). These I try and split between two French Divisions if using both so as to maximise the potential for generals to join them for combat re-rolls.
Have the Neapolitans worked ? Not really, IMHO. Quite apart from any other qualities, the Garde d'Honneur uniforms also nicely match my luggage. But in gaming terms the poor conscript line infantry are really not much more than a speed bump for any opposing units - there is no point in tooling them up with attachments, and why use them in the front-line when the French conscripts are better at it and actually moderately effective. 60 points is a lot to spend on luggage (LoC) guards. The poor drilled Velites LC are hard to use effectively cos they really aren't front-line troops either, though potentially make a useful 'skirmish' screen on one flank. And, while the Garde have cool-as uniforms, they really have failed to be truly useful on the attack. To be fair to all those "guards are far too effective" advocates out there (you know who you are

), the Garde really are great as a 'blocker' on the edge of any main attack - as guard they are hard for an opponent to bust quickly, and they do keep bouncing back. But, as poor drilled, they also don't rally that well, nor dish out much harm.
So, on balance, I would say that the 33eme Divisione de Napoli allows for a better mix in the rest of your army selection, but not a whole lot in terms of game effectiveness (which is exactly what you'd expect given their cheap points costs). But, as has been poined out, the Neapolitans do have pretty uniforms and standards, and they aint in bleu !! Sadly, this is possibly the bestest recommendation for including them

.
The Swiss are a whole other story - generally they end up at the pointed-end of my attacks, and while they have had some very bad bloodied noses, they have more often dished out the same and contributed to good results. And they aint in bleu either !