Most varieties are seasonally oriented with sakura (cherry, sort of) being on the shelves right now, and strawberry being the year-round favorite way to spice up the mainstream versions of everything. In the U.S., I think this is also common. If it works in its pure form, try it again with strawberry. In Japan, the next phase is to do it with green tea. In the U.S., it tends to be making it with peanut butter next time around.
It is clear that fake strawberry seems to be a world-wide crowd pleaser and my husband wanted to try this one. Well, he wanted to try it and play a UFO Catcher game (crane/claw game) for fun and this was a reasonably acceptable prize. That means I paid for this without buying it in a store, but these are readily available in supermarkets all over Japan. If they aren't currently available, you can rest-assured that they'll come back in the rotation again soon enough. It is as inevitable as the tides, and smutty jokes on The Impulsive Buy by Marvo.
Pitting a Lotte Custard cake against the likes of these would be like pitting a donkey in a race with a champion thoroughbred.
I favorably reviewed Lotte's original custard cake taking it at face value. That is, I didn't compare it to beautifully made hand-designed cakes. It's important to remember that 6 shelf stable packaged cakes for tossing into a backpack or desk drawer aren't meant to rival something from the fancy cake shop that you can't shop at because each of them costs more than your usual lunch at Subway (note: I did not buy the pictured cakes, but was given them as a gift by a generous student).
The strawberry version was just as "good" as the plain version in that it was a serviceable sponge cake with cream filling that had the air of preservation in its foil confines. However, there were 6 cakes in the box and only one of them had a decent amount of well spread strawberry on top of the cream. The remainder had just a smidge off to one side. This didn't in any way make them less pleasant, but if you were in it for the strawberry, you'd be bound to be just a little disappointed. The one cake which did have a reasonable amount of strawberry reminded me of the cheap disc-shaped sponge cakes with an indentation in the middle that my mother used to buy in 6-packs for strawberry shortcake. We'd make them by putting a modest amount of berries in the center, a heap of sugar, and then pouring whole milk on them for a soggy treat. It was good in the way that cheap things can sometimes be good despite not actually resembling honest "food".
I enjoyed these much as liked their plain sibling, but the truth is that I probably wouldn't buy this particular version again. If all of them had as much strawberry goo distribution as the one "winner" in the box, I'd buy a box again for the nostalgia reminder from my childhood. As it is, I think I'd just as soon go with the regular version since they can't get their machines to squeeze out the strawberry properly.