Despite mounting pressures over its iPhone X, Apple is still a compelling buy, according to Craig Johnson of Piper Jaffray.

A report by Taiwan's Economic Daily earlier this week that Apple would cut its forecast for the iPhone X sent Apple shares tumbling 2.5 percent on Tuesday. The stock failed to recover from those losses on Wednesday morning. But the technician says that based on his charts, the stock still has far to go before it's in trouble.

"From my perspective, we've got nothing wrong with the chart," Johnson said on CNBC's "Trading Nation" on Tuesday. "So all we've done is seen a little bit of profit-taking here."

"We'd have to see a close below $165 to violate the uptrend support line that has been in place for more than a year, and break $155 to take out the 40-week moving average," he added.

This means that Apple would still need to fall another 9 percent for Johnson to believe it might be time for investors to think about selling the tech giant.

Chantico Global CEO Gina Sanchez, however, believes that fundamentals are suggesting that the iPhone supercycle may be over.

"Apple is fulfilling their [iPhone X] orders on a next-day basis, which tells you that there's no wait time anymore," she said on "Trading Nation." "That's probably not a good sign for Apple."

"This is a strong franchise, and I think they still have lots of ways to monetize what they have, but it's probably a wait-and-see right now," she added. "[The stock isn't] expensive, [it's not] cheap, the fundamentals are going to reign, but we still don't see any big catalyst."

Still, Apple has surged 47 percent this year.