Kind of funny that I hear the song, "My favorite Things," from Sound of Music in my head when I read this topic headline.
I've attached a photo of some of my favorite toys, which tend to range in the 9" to 12" insertable range for length, and anywhere from 2" to 2.5" in girth, although not always in the same toy. This is by far only a small example of the the rather large collection I have of probably about 50-60 dildos in various shapes, sizes, textures, and densities, including some that are insanely large which are rarely, if ever, used.

- MyFavoriteToys.jpg (139.55 KiB) Viewed 5647 times
When I'm craving depth, I'll go up to 17" of more in length, although it has to be tapered (Venomous Tongue & Sigmaloid) and/or fairly flexible and slim on the head, to make it into my tranverse colon that far. When I'm going for strong girth action, I reach for my Tantus Hoss and Tom of Finland's Kake Cock (both fairly firm).
The toys I use during my normal cleansing routine in the shower include those 6 toys on the right of the photo: the 18" double header tapered dildo, Nabini 12" dildo, and all four of the Pipedream dildos pictured. Each has its own feeling and purpose during my cleansing process, which tends to really make me aroused, stimulating my prostate to generate hands-free cummies (different than cum), and sometimes make me actually cum really hard before leaving the shower. After than procedure, I tend to remain clean for at least 12-14 hours, without any worry about anything getting messy.
I suppose if there were two toys to pick that are my favorite "go to" toys that always work for me, they're the 12" Nabini and the 11" Pipedream KC Ultra. The Nabini unfortunately has been discontinued by Amazon, and when I tried to order another I received a cheap imitation that was exactly the same in all ways except the density. It was way too firm and not softer like my original toy.
My favorite tool for my toys is one of my three fucking machines that can handle big toys and has a pretty good range of various speed, angle adjustments, and thrust depth options that can be quickly changed.
Overall, there is no one toy that is my favorite, just as I would not eat only one type of food, because I sometimes often prefer different types of foods (Italian, Mexican, Japanese, French, etc.). This is the same for sexual preferences to match the moment, where I sometimes just want to go with nothing more than my basic cleansing toys, other times I crave depth or girth stretching. Most times, larger toys feel better when they're more flexible (and less chance for accidental injury), and smaller toys when they're more firm (so I can't involuntarily push them out when the urge takes over during intense sessions).
Hey, why limit my favorite to just one toy?