Hi Katie and welcome to the forum! First, I'll correct your IDs. The first one is Hoya DS-70 (it is commonly sold with the name burtoniae). I can't read the tag on the second, but I think it might be right - australis, but it's a variegated form. (Nice one, BTW... I don't see that one often!)

I always repot plants when I get them for a variety of reasons. First, I want to see that the root system is healthy. I don't like it when plants are top dressed with rocks for the very reason you state - you can't tell when it's dry, and it's likely keeping it from drying out fast enough. I also prefer it be in the mix I grow in because I know how to water my mix whereas a different mix might dry out faster or slower. And lastly, quite often growers put plants in larger pots for the purpose of charging more for them and when I unpot them, I find the root system is WAY to small for the size of pot, which will mean sure death because it will stay wet too long. When you unpot them, just try not to disturb the root system too much when you pot it into new mix. A lot of plants can handle their roots being man-handled, but Hoyas are a little less forgiving. I make it a point to treat them with kid gloves, especially when they're young like yours.

Hoyas need a loose mix, so if you're going to use a all-purpose mix, just add some perlite to it to give it a bit faster drainage. When watering young ones, I don't let them dry out completely, but they do need to approach dryness. I think you'll find them pretty easy to grow.

Denise in Omaha

I appreciate the info, I will get them repotted soon! Yes it is labeled Australis, they had three and I was tempted to get 2 and combine but I resisted temptation. :). Do you think it will send up new stems over time if given the right conditions? Is it a slow grower? Thanks again!